JPH02979A - Post treatment of relief plate developed for use in flexiso printing - Google Patents

Abstract

PURPOSE: To rapidly decrease the tackiness of a solid polymer layer by treating the layer with a solvent containing aryl- of hetaryl-bis-trihalogenomethyl-s- triazine. CONSTITUTION: A relief printing plate after developed is treated with a soln. essentially comprising an org. solvent and aryl- or hetaryl-bis-trihalogenomethyl- s-triazine expressed by formula I dissolved in the solvent, and then dried and exposed again to UV rays in a short time. In formula, Y represents an aromatic or heterocyclic aromatic group which may be partly hydrogenated with a conjugate alkenylene chain, and further, which may have substituents, and (K) is chlorine, bromine or iodine atom. Thereby, the post treatment to remove the tackiness of the surface of a printing plate can be fast and easily performed without using a corrosive soln. and the stability of the printing plate against ozone-contg. air is permanently increased.

Description

DETAILED DESCRIPTION OF THE INVENTION The industrial field of application is a developed relief printing plate theta processing method VcLAI for 7-lexo printing, which is conventionally described as 84 yuan.

Prior Art -) A photosensitive 7-layer printing plate is made of a multilayer material. In the case of ninety pieces, it is generally a thickness of 0.5 to 7JI containing a dimensional support material, an elastic binder, an elastic binder, a monomeric initiator, and additives.
It consists of a polymeric or photocrosslinkable elastic layer of II, a tack-free cover layer (combined overcoat) and a separable protective film.

The support may consist of metal or of a transparent plastic film, preferably of dimensions f.

The support material is useful for reinforcing and maintaining the dimensional integrity of the millimeter thick elastic layer during the printing process. In order to firmly adhere to the support material without hardening, a ship ffi layer is necessary, for example, the West German National Watch Publication No. 31 LIOI No. 75 INfa,
One-component or two-component systems based on polyurethane or polychloroprene as described in I3107741, Saimei No. 2444118 Saimei Ryokama and M3137416 Saimei No. It (
U.S. Pat. Blends of polyesters with polyamides, polyurethanes or polyolefins are disclosed. West German Discharge Order No. P 5740452.6 discloses a layering compound with chlorosulfonated polyethylene f:.

When exposed to light according to the photosensitive 7 lexographic printing plate of this series, the area of 1 mound of the light Jl [substance no] will be exposed or photo-corroded. After removing the uncured layer area with a suitable bath agent, a rubber-elastic relief printing plate is obtained,
This can generally be further cured by re-exposure with chemical ◎ On the vIi1 surface of the Moonrin complex layer, the light λ light progresses only incompletely, probably due to the high degree of maturity there. Incomplete AL coating is evident by sticky printing & surface.

The sticky, sticky surface is disadvantageous when this plate material is used as a printing plate. During the printing process, for example, paper burrs adhere to the buildup board, with the result that the quality of the print is degraded. On the other hand, it is the inner cone that separates from each other when the sheet metal is expanded.

Various methods can be used to overcome the disadvantageous surface layering properties. Post-treatment with water bath solutions containing free halogens or halogeno-releasing products JX is common in practice6. for example,
The printing plates t-Na0C1 and HC't are immersed in a water bath solution, or a bromine solution (West German Patent No. 8A), a bromine solution containing a wetting agent (West Germany)
Release No. 2521955 #1A11 or iodine bath solution (
West Germany 1st Edition Publication No. 3L171141-Q Specification ★] can be processed. Two true treatments, first in a VC bromine or iodine bath and then in a VCNa0Ct bath, are recommended (tfF No. 01 at the time of European publication).
: J96835 Ming Sai Ming = Yoneda Jicho No. 4451553 Ming No. Ming].

However, this solution is aggressive and contains corrosive properties.

At the same time, it is also possible to treat the printing plate with a bath of carbonylated compounds that form free radicals under the action of a UV chamber and then to irradiate it with short-wavelength σV radiation (US watch M42
02696 highest honor). However, this method is harmful to health and requires a special light for its generation, σV[(20
0 to 300 nm) has disadvantages.

Furthermore, the exposure time is relatively long (up to 15 minutes).

According to another method, the adhesive JIIIR is immersed in an aqueous bath containing a violet and a photoinitiator and then exposed to AV4VC (WO 86/L) No. 2177. #
A★).

The disadvantage of this method is that it requires special equipment such as axial IRO and that the solutions or dispersions used are not stable.
Ru.

Furthermore, the printing plate is inactivated, #note binder, light single combination, note single product, and light interval #! It can be coated with a solution containing tungsten and exposed to UV light for a long time (West German Tit Patent Publication No. 3,704,067).However, this layer is relatively hard and has a tendency to reduce the flexibility of the printing plate. lower.

O post-treatment in the most widely used A element-containing baths does not suffer from the above-mentioned drawbacks, but also increases the crack formation of printing plates when in contact with ozone-containing air. Crack formation renders the printing plate unusable. The nature of cracking and its device depends on the composition of the elastic optical 1 coalescing layer. Crack formation can be lowered by using an antiozonant, a lubricant, and a nidistomer that does not contain an olefin double-layer. However, it is difficult to find suitable compositions of sII injections in relief printing plates which have good mechanical stability during photopolymerization and at the same time low sensitivity to ozone. Ru.

On the commercially available 7 lexo printing plate of Genmu Bontai, Kouri @ Hetai no is still 11! Stability against ozone even if it contains an antiozonant of Iji1/&
-Needs improvement. Therefore, various post-treatment methods have been developed29 to prevent the formation of cracks during the storage of printing plates which have already been rendered inactive.

One method is to treat the printing plate with a solution of nickel- or zinc dialkyldithiocarbamate O in an organic solvent. It has the disadvantage of being dangerous.

According to another method, the relief printing plate is coated with an alcoholic polyamide solution (West German Kunamisaki Publication No. 3415
044, or by treatment with liquid polyglycol ether (West German Publication No. 3512632).

These methods protect the printing plates before the printing operation and even after warping, but during the printing process the storage that protects the printing plates from ozone is washed away by the printing ink layer.

Problems to be Solved by Egl Therefore, the object of the present invention is to - be carried out quickly and easily, - without the use of corrosive baths, - to improve the stability of printing plates against ozone-containing g!, air, etc. It is an object of the present invention to disclose a method for post-processing printed printing plates, which permanently increases the adhesiveness of the printed printing plate and eliminates adhesive coating on the surface of the printing plate.

SUMMARY OF THE INVENTION It is an object of the present invention to obtain a developed relief printing plate Ltl for use in 7requin printing, which has been re-exposed in a conventional manner.
69, the method is disclosed in 69, the method is a commercial leaf #] printing plate, mainly an organic solvent and the aryl- or hetary-rubis-trihalo r of the general formula 1 dissolved therein. The relief printing plate is treated with a solution consisting of trimethyl-a-triazone and the relief printing plate is cured for a short period of time U.
Including re-exposure to v#.

The method of the present invention is advantageous in that it is applicable to all light-cured, adhesive-filled #J printing plates that contain a magnetic compound and have a sticky adhesive surface. In general, the method is suitable for reducing the viscosity of solid polymer layers.

In the compound of general formula 1, Y is an aromatic or heteroaromatic, optionally substituted with tIt, optionally F) at the 9 position of the A-role alkenylene chain (
Cs to Cs) Alkenylene gold flake or unsaturated ring -C
- a group which has been partially hydrogenated by Mf through an atom, and which can be further modified directly by mft, especially by aryl or by Ar(CB''-Ca) alkenylene. and K represents a chlorine atom, a bromine atom or an iodine atom, in particular a chlorine atom.

Examples of suitable It substituents include: halogens, especially chlorine and 7-aryl groups, nitro groups, sulfonyl groups, alkylmercapto groups, phenylmercapto groups, acyl-sensitive aryloxy groups, hydroxy groups and especially alco A''/M
* (CaNO8) which is preferably substituted by halo, phenyl or phenoxy and each methylene group may be replaced by a 〇- or S bridging group, an alkoxy group, a phenoxy group, a cyclo Alkoxy i and alkenyloxy groups.

Convenient aromatic groups include phenyl-attached, bicyclic or polycyclic groups, and also include heteroaromatic compounds.

Examples of suitable aromatics include: naphthalene, anthracene, 7-enanthrene.

Quinoline, isoquinoline, benzofuran, benzobirane, zobenzo7rane, benzothiophene.

Zobenzothio7ene, acenanthene, penguoxazole, fluorene, tetrahydro7enanthrene and hihydro7enaline.

When Y represents an aryl group or aralkenyl St-,
This group is a helogne, especially a radical, an alkoxy, especially (CI
S-06) Alkoxy, alkyl.

1ic(C1-C4) is advantageously substituted by an amine which may be di-substituted by furkyl, allyloxy, hydroxy or alkyl.

When aryl is phenyl, it is advantageously substituted in the 2- and/or 4-position, but also in the 3- and/or 4-position when the substituent is alkoxy.

The above-mentioned substituents may also be applicable when Y narrows the alfurkenylene group containing (CaNO3) y-lkenylene gold. Styryl and 7-enyl detazoenylated derivatives are particularly suitable.

Its younger sister is nistyryl-4-mef, which has a similar aromatic group linked to the triazone ring by an alkenyl group.
Rustyryl, distyryl in 4-chlorosteryl-2-hydro, 4-methoxysteryl-4-6-butoxystyryl-4-amyloxystyryl-4-7lyloxysteryl, 6-medoxy-4-hydroxy-styryl-
2,4-zomethΦdistyryl-6,4-dimethoxystyryl-4-zomethylaminostyryl, phenyl-butadienyl-4-dimethylaminophenyl-butadienyl and 3-(N-ethyl-benzoxasilyl-2-ydenyl) )-propen-1-yl-0 Y represents an aryl S which is not attached to the triazone ring via an alkenyl group, and this aryl group is phenyl, naphthyl or the above-mentioned bicyclic or polycyclic group, or It is advantageous to use one of the heterocyclic compounds. This may be substituted with aryl or Ar (C2-C6) alkenyl, which has the same general properties as before. This Itf! When the aromatic group bearing the A group is 7enyl, substitution by Ar(C2-Ca)alkenyl is preferred. Particular preference is given to the Ar(CB)alkenyl group, especially when this substituent is present in the 4-position.

In particular, the aryl used in this case is phenyl.

Examples in which Y represents phenyl substituted by II&s VC are listed below: phenyl-4-chlorophenyl-4-methoxyphenyl-2,4-dichlorophenyl 4-phenylphenyl-0 YdjAr(Cl-Ca) Example f of phenyl substituted by alkenyl: 4-styrylphenyl-4-p-/)xystyryl-phenyl-4-p-methylstyryl-phenyl-4-p-
/lorostyryl phenyl-4-o-/colosteryl-phenyl 4-m-chlorostyryl-phenyl-4-p
-bromostyryl-phenyl-4-m.

p-1 methoxystyryl-phenyl-4-p-! )l/
Styryl-phenyl-4-m B mgP-)rimethoxysterylphenyl-4-p-hexylstyryl-phenyl-6-chloro-4-steryl-phenyl-5-/chlor4-m-chlorostyryl-phenyl-6 -chloro-
4-p-methylsteryl-phenyl- and 2-styryl-phenyl-0 When Y is a naphthyl group, it has the general formula fl: [wherein Yl is frozen candy or -0Y3. Especially oy3t-niwashi, Y,
is H, CL, Br, lower alkyl 1. alkenyl group, aryl group or optionally substituted ( C1
″-C,) alkoxy group s!A'ic hydrogen.

(C1-03) represents an alkyl group or a (Cz-C3) alkoxy group, and Y3 may be ffltm-substituted by a halogen, especially chlorine or an X element, an aryl group or an aryloxy group, and each methylene group is CCx-Cm) alkyl groups, cycloalkyl crystals, alkenyl groups or aryl groups, in particular (Cz-C4) which may be replaced by O or S
It is represented as an alkyl- or alkoxyalkyl group, or Yl and Yλ together represent an alkylene group T:
In particular, this corresponds to the formation of a 5- or 6-membered ring with the naphthalene nucleus.

Also suitable are compounds in which the 8-triazonyl group and the alkoxy group are present in the 1,4- or 2,6-position of the naphthalene ring.

The number of carbon atoms contained in the alkoxy group is 0, which does not significantly affect the photochemical action of the initiator, and the restriction to 78 C atoms a in -0Y5 is not strict; for example, nonyloxy 2i! , dodecyloxy or octadecyloxy groups.

Specifically Yrl, including the missing naphthyl group: 7-1-yl-2-2-methoxynaphtho-1
-yl-4-methoxynaphth-1-yl-5-methoxynaphth-1-yl-14-ethoxynaphth-1-yl-
4-Butoxynaphth-1-yl-11-methoxynaphth-2-yl-6-medoxynaphth-2-yl-96-nodoxynaphth-2-yl-6-nitoxynaphth-2-yl-4,5-dimethoxynaphth-1-yl- 4,7-dimethoxynaphthol-1-yl-4-(2-methΦdiethyl)-naphthol-1-yl-4-(2-ethoxyethylnaphth-1-yl-4-(2-cytoxyethyl)-7
To-1-yl-5-methyl-6-medoxynaphthol-2-
yl- and 4-(2-ethoxycouethoxynaphtho-1
-・f Roux.

Yl and Y2 together form an alkylene group,
In particular, the compounds it forms with 5- or 6j4m when attached to the naphthalene core are also sometimes collapsed. Preferred is acenaphth-5-yl.

Other polycyclic groups represented by Y include: 4-methoxy-andran-1-yl-7 enantio-9-yl-, benzopyran-6-yl-quinol-3 −
yl- and zobenzochen-6-yl - Compounds corresponding to the general formula I are known69, e.g.
im*).

U.S. Patent No. 3954475 r# (=West German Patent Publication No. 2243621), U.S. LnSpec a'Fi
No. 4239850 QM Homare, Nishi Toy Y (5 Patent Publication No. 27
No. 18259 #: i', F! jiGermany! #Publication No. 2934758, West German Patent Publication Jg
3337024 It is listed in the most important feature.

Range 300-5 [J Onm It is possible to use a 7 Leeru or Hetary Rubis-trihalologtumethyl-5-) lyasin containing a K absorption peak.

How not to invent! ! i! In i-, it is also possible to use mixtures of several, in particular two or three aryl- or hetaryl-bisutrihalotrimethyl-B-, triazones.

The bath additives that can be used for the above-mentioned triazine bleached conductors include most of the solvent-based solvents, such as aliphatic and aromatic hydrocarbons, such as aliphatic and aromatic hydrocarbons.

Ethers, esters, ketones, alcohols, trimethylformamide, etc. A mixture of at least two different solvents!
Jt can also be used. Chemicals which have good melting power, are easily volatile, and are physiologically safe, such as toluene, tetrahydrochloride, ethyl acetate, methyl ethyl ketone, etc., are stirred.

Triazone derivatives in solvents exhibit widespread summer movement.
, 0.1λt% to the total cell value. Isora 2
-15 iL%, especially when used in baths with 2 to 7 ml of smoke.

The treatment solution according to the present invention may also contain a soluble binder and a soluble dye. Suitable binders include non-laminated cliff base 2, such as vinylidene chloride conjugate, cyclized rubber.

polycarbonate, polyacrylate, polystyrene,
Examples include polyamide.

7! J-Lux Matata U Tally Rubis-Trihalo-r-methyl-〇-Triasif 1 part binder Ll, Ll
1 to 1 part, in particular 0.05 to 0.5 parts, can be used. In comparison, the 4tn binder Miyakura produces a non-viscous pour coating gold printing plate that can be easily removed with a solvent.

By adding a binder, the X-gold body participates in lowering the Vi layer properties, so that the degree of aryl- or hetarylupisotrichloride methyl-8-triazone can be lowered. Generally up to 50% triazine derivative t
It is possible to substitute the binder without impairing the advantageous customization properties of the process according to the invention. Triazo/#sI
Replacing part of the conductor with a binder has the advantage of reducing the cost of the processing solution.

As a photocuring compound contained in photocurable 1-
L-magnetic gold bodies also contain gold, which either crosslinks itself upon exposure to light or becomes opaque with the aid of the photosensitive crosslinking agent VC. In particular, the photocurable layer is a photocurable layer containing, in addition to an elastic binder, an ethylenically unsaturated radically polymerizable compound and a photoinitiated compound that forms free radical gold upon exposure to light. Mixtures of this type are known and are described, for example, in the above-mentioned publication Md.

The elastomer that can be used is any type of natural or synthetic rubber. Vinyl Glock colum body 2
For example styrene and dienes.

If you line them up, they are soaked in butadiene or isoprene.

-i, acrylic acid- or methacrylic-related esters of polyalcohols, such as hexanezool/'-1,6-zoacrylate and hexanediol-1,6-methacrylate [t] monoethylenically unsaturated monofiltration; Use it as a body. However, the layer may also contain other esters of acrylic acid and methacrylic acid with monohydric or polyhydric alcohols. Historically, other unsaturated monomers, such as vinyl esters or maleic esters of aliphatic monocarboxylic acids and CF7 malic esters, etc. r'I5! It can also be used.

1 elastic binder and 0. U
Use 5 to 0.3 parts.

Many substances can be used as Q Genkai during Calm Paralysis, Ca punishment. Examples are the basic substances benzophenone, benzoin, pencil, pensol monogatar, fluorenone,
Thioxanthone, polynuclear quinones, those derived from acridine and quinoxaline, and trichloromethyl-8-
Triazone, a carbonylmethylene heterocycle containing a triherotmethyl group according to West German IA Publication No. 3333450, or e.g. West German Special Publication No. 3
7-sylphosphine oxide compounds as described in the specification of 133419. Generally, the initiator is used in an amount of 0.01 to 10% by weight based on the non-volatile JA component of the layer, and 0.05 to 5X''i of JA.

History V, Genrokukai note no is I? It may also contain notes that improve the reading, suggestion behavior, and other countermeasures and notes. Regularly used small IN
:J-mono, for example, an inhibitor that prevents heat storms.

Dyes, antioxidants, antiozonants, silkworm MIJ and 'iX families.

The element j@conjunction may be uniform or may consist of a number of mutually λ mutually symmetrical planes with different 111i. For example, it is possible to use a photopolymerizable resin consisting of two layers, in which case the layer facing away from the support is also hard. In general, the total thickness of the photopolymerizable layer ranges from 0.05 to 7 mm, in particular from 0.2 to 5 mm
It is i+.

As is known in the art, the photopolymerizable layer is an inert, LF-prone, thin lambda fraction, e.g.
41 can be overridden with a thicker strippable protector made of J' bath-based polyamide. -J - Polymer J-
has a thickness of 1 to 2 μm and a protective film has a thickness of approximately 50 to 200 μm.
Load m warehouses.

As an excellent and dimensionally stable support film for a nine-metal body, a transparent Norasnak film 1 having a thickness of 50 to 3 LIO .mu.m, such as a film made of polyester, polycarbonate, polyimide, etc., is conveniently used. Polyethylene terephthalate films are particularly suitable. When the support material is placed between the base plate and the rubber elastic base sheet, the thickness may be thinner than that of the support R#V, for example, down to 10 μm. Generally, different sides of the polyethylene terephthalate film are overlaid with a contact layer or a layer containing a contact promoting substance.

A photopolymerizable layer with a thickness of 0.5 to Z 9 mm - by evaporating a solution of the layer components or by forming a material crosstalk between parallel plates, or by any known method. It can be produced by extrusion through a wide slit nozzle and then calendering the strip. When producing the photopolymerizable layer according to the last mentioned method, it is advantageous to bond said layer to a support film and a protective film that fit together while in a calender when hot. be.

If a non-photosensitive soft rubber sheet or an elastic 7 ohm sheet is applied to the back side of the support film, it should be applied with a Vc contact layer on both sides of the support film. The contact layer on the back side of the support film is the same as before bonding with the support film C base compatibility layer.
It can be administered during or at that time. lamination) k1
During the lamination process, the skin can be covered with an easily peelable film to protect it from dirt on the roll of the laminating machine.

The multilayer flexographic printing plate material is processed by the t-f method to produce a ready-to-use printing plate. First, a printing plate substrate is produced by uniformly exposing the printing plate material through a support film. After peeling off the protective film, -A@J on the opposite side
is exposed through a negative film original. Thereafter, the unexposed, uncured areas are removed with a suitable developer, for example with a crystallizer of perchlorethylene and n-butanol.

The laminated elastomer printing plate thus produced is first processed using a known method, for example, using a 32Ll Watt fluorescent lamp (620W) C7V lamp, which is generally used in the production of printing plates.
The cross-linked film was re-exposed for 1U using an exposure device equipped with
6 is completed, and then the process according to the present invention is performed to eliminate the sticky bond. Re-exposure should be done prior to fall processing. This is because, during the post-treatment according to the invention, the aryl- or hetaryl-bis-trihalobutsumethyl-5-)lyazo/ present on the printing plate does not contain the necessary chemistry to further promote the linkage. This is because it will be absorbed.

The processing according to the invention of the re-exposed, still sticky printing plate can be carried out in different ways.

The yv-ru or hetary-ruby-suit v-apy' methyl-a-triazone solution can be sprayed onto the printing plate, brushed or rolled with a suitable soft absorbent roll.

However, it is also possible to immerse the printing plate in the TM solution. The treatment time may be from 1 second to several minutes. The higher the @ degree of the solution used, the shorter the processing time. Normally, am equipped with approx. 5
Approximately 10 seconds of soaking is sufficient for a V11 meeting using a λtchi idiom.

The printing plates treated with these solutions are allowed to dry. If a readily volatile solvent is used, it can be left in the entire printing plate for a short period of time to dry.

However, it is also possible to dry the printing plate by exposing it to hot air or by placing it in a heated phase.

Place the mixture in a pan so as not to reach the decomposition temperature of the 7-methyl-8-triazine. Temperatures below 120° are preferred.

Often, even after evaporation of the solvent, printing plates treated with aryl- or hetaryrubis-trihalogen)tfA/-9-triazone solutions are still sticky. In that case, the printing plate is re-exposed to long-wavelength σV light for a short period of time; only the * minute will result in a non-stock increase order. Any original that emits this oak light mk can be used for this purpose.

For example, fluorescent tubes, water/steam lamps and metal heronide lamps may be mentioned in this connection. The amount of light required for re-exposure of the processed printing plate is approximately 1 U% of the amount of light required to form the relief formations.

The reaction mechanism that also reduces the viscosity 7fI property is still not clear. The surface of the printing plate is wet-faded during processing. Even if you wipe it with a solvent, it will not return to its sticky state.

EXAMPLE Next, the excellent aflll of the present invention will be explained in detail. Unless otherwise stated in the book, 9, the ``俤'' and ``maiwari'' in the pan are related to heavy electric units. “'JL] it department” (pbw) and “
The capacitance part J (pbv) has a relationship of riJ and r cm'' J and O.

Examples 1 to 5 Commercially available 7 lexo printing Jll of 5 types of plates II! The exposed and uncured unexposed areas corresponding to the I7 images were each washed using a suitable commercially available developer. The printing plate was then re-exposed to a T-320 Watt UV lamp for 10 minutes. The still viscous 7JI printing plate was then treated for 10 seconds with a solution of 6x amount of 2-stilbenyl-4,6-bis-trichloro1fk-8-)177 in toluene according to the method of the invention, i.e. the bath liquid The sample was immersed in the liquid, dried for a short time, and then exposed again to light, this time using the UV lamp mentioned above for 2 minutes.

This plate showed no tackiness on the surface. Additionally, it has a relatively high resistance to ozone. To test resistance to ozone, the printing plates were placed in a box and exposed to 0.4 ppm ozone-containing air at room temperature.

The test Wa is listed in the following formula.

Examples 01-C5 The commercially available flexographic printing plates used in Example 1S5 were exposed and developed as described above. Next, the obtained printed sheet metal was immersed in a 0.4][t% odor-containing aqueous solution as known in the art, washed with water for 10 minutes, and then washed with water for 10 min. I then re-exposed it for 10 minutes using a 620 watt 07 lamp.

These versions also did not show kaimen kudan・sha, but examples 1 to 5
Contains ozone as shown in ml! When processed with fi,
It showed significantly lower resistance than the plate according to the invention.

Try @Yumi to the temperature range in Kudan.

The 7 lexo printing plates were processed for the times listed in the table to allow time for O1 & cracks to initially occur on the plate when treated with ozone. Re-exposure time was 10 minutes. The printing plate was then dissolved in 2-stilbenyl-4$6- in toluene.
It was treated with 4% by weight of bis-trichloromethyl-a-lyasin and 11 amounts of cyclized rubber for 20 seconds.

After re-exposure for 2 minutes in a 12U UV lamp, a non-tacky 7# printing plate was obtained, which had excellent resistance to ozone-containing air.Examples 7-9 Commercial flexographic printing plates Su, 1 v le (Cyrei■)
Hl, 831! l Gold version original, current thick and example 1-51/)
Like re-exposure and mourning. Each plate was then treated with one of the aryl-bis-trichloromethyl-8-triazones in toluene for 15 seconds.

Example 6 Commercially available 7rekin printing plate Cyrsl (Cyrsl■) HLS
(Du Pont) as described in Examples 1 to 5 and corresponding to the exposure equipment used, it was viscous and ozone-containing.
The following exposure times are required to produce a printing plate with excellent resistance to V2 gas.

The printing plate was dried and reexposed for 6 minutes using a 120 watt UV lamp.

The printing plates obtained in each case had a non-viscous layer and were resistant to ozone-containing air.

Good results were also obtained with mixtures of these triazone derivatives. The mixing ratio can be varied within a wide range depending on the requirements of the commercially available flexographic printing plates used.

Examples 10-12 Cyrel@ HLS m commercial 7 lexo printing plates were exposed, developed and re-exposed as in Examples 1-5. 2-Stilbenyl-4 in printing sheet metal toluene,
6-bis-trichloromethyl-8-triazone, 63[
It was treated with ff11M solution.

Claims (1)

[Scope of Claims] 1. A method for post-treating a developed relief printing plate for use in flexographic printing, which has been re-exposed in a conventional manner, wherein the relief printing plate is treated mainly with an organic bath agent and General formula I dissolved therein: ▲Mathematical formulas, chemical formulas, tables, etc.▼(I) [In the formula, Y is an optionally substituted aromatic or heteroaromatic conjugated alkenylene chain. represents a partially hydrogenated group which may be bonded via an unsaturated C atom in the ring system or via an unsaturated C atom in the ring system, and this group may be further substituted, and K is a chlorine atom, a bromine atom or an iodine atom. aryl- or hetaryl-bis-trihalogenomethyl-s-triazine with the atomic symbol ], drying of the relief printing plate and subsequent re-exposure to UV radiation for a short time, For use in flexo printing,
Post-processing method for developed relief printing plates. 2. The method of claim 1, wherein the aryl- or hetaryl-bis-trihalogenomethyl-s-triazine compound is contained in the solvent in a concentration ranging from 0.1% by weight to the saturation value. 3. The process as claimed in claim 1 or 2, wherein a mixture of various aryl- or hetaryl-bis-trihalogenomethyl-s-triazines is used. 4. A process according to claim 1, wherein the aryl- or hetaryl-bis-trihalogenomethyl-s-triazine has an absorption peak in the range 300-500 nm. 5. The method as claimed in claim 1, wherein the after-treatment solution additionally contains a binder. 6. The binder consists of a non-stick polymer, and the polymer is present in the post-treatment bath in an amount of 0.01 to 1 part per part of aryl- or hetaryl-bis-trihalogenomethyl-s-triazine. 6. The method of claim 5, comprising: 7. The process as claimed in claim 1, wherein aliphatic or aromatic hydrocarbons, halogenated hydrocarbons, ethers, esters, ketones and alcohols are used as solvents.